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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hello Felipe,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>What do you mean by “process base versus CORS”? Do you mean running rtknavi with the CORS as an input?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The Rover was operating within 30m of the base, but I can try it closer if that would help.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>On the next test, I will let the Rover idle for a while before starting the test. The antenna (or rather the steel plate) is the highest point on the robot (by about 30cm). The base, however is rather low to the ground and I am trying to build something to elevate it more.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>-Sean<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> foss-gps-bounces@lists.osgeo.org [mailto:foss-gps-bounces@lists.osgeo.org] <b>On Behalf Of </b>Felipe G. Nievinski<br><b>Sent:</b> Wednesday, September 17, 2014 9:50 PM<br><b>To:</b> foss-gps@lists.osgeo.org<br><b>Subject:</b> Re: [FOSS-GPS] Mobile Robot Experimentation<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>before anything else, check what accuracy you get <o:p></o:p></p></div><div><p class=MsoNormal>with the rover parked for a couple of hours. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>to isolate which one between rover and base <o:p></o:p></p></div><div><p class=MsoNormal>is noisier, download data from the nearby CORS, <o:p></o:p></p></div><div><p class=MsoNormal>then process your base versus CORS and your rover<o:p></o:p></p></div><div><p class=MsoNormal>versus CORS separately.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>keep your base as close as possible to the rover.<o:p></o:p></p></div><div><p class=MsoNormal>that's the best way to mitigate iono delay <o:p></o:p></p></div><div><p class=MsoNormal>without dual-frequency tracking data.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>turn on the GPS on the rover for some time <o:p></o:p></p></div><div><p class=MsoNormal>before it departs, as it should help with <o:p></o:p></p></div><div><p class=MsoNormal>ambiguity resolution.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>try to elevate the antenna above the body<o:p></o:p></p></div><div><p class=MsoNormal>of the robot, so as to minimize multipath <o:p></o:p></p></div><div><p class=MsoNormal>and EM interference.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On Wed, Sep 17, 2014 at 6:06 PM, <<a href="mailto:foss-gps-request@lists.osgeo.org" target="_blank">foss-gps-request@lists.osgeo.org</a>> wrote:<o:p></o:p></p><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><p class=MsoNormal>Send FOSS-GPS mailing list submissions to<br> <a href="mailto:foss-gps@lists.osgeo.org">foss-gps@lists.osgeo.org</a><br><br>To subscribe or unsubscribe via the World Wide Web, visit<br> <a href="http://lists.osgeo.org/mailman/listinfo/foss-gps" target="_blank">http://lists.osgeo.org/mailman/listinfo/foss-gps</a><br>or, via email, send a message with subject or body 'help' to<br> <a href="mailto:foss-gps-request@lists.osgeo.org">foss-gps-request@lists.osgeo.org</a><br><br>You can reach the person managing the list at<br> <a href="mailto:foss-gps-owner@lists.osgeo.org">foss-gps-owner@lists.osgeo.org</a><br><br>When replying, please edit your Subject line so it is more specific<br>than "Re: Contents of FOSS-GPS digest..."<br><br><br>Today's Topics:<br><br> 1. Mobile Robot Experimentation (Sean Hyde)<br><br><br>----------------------------------------------------------------------<br><br>Message: 1<br>Date: Wed, 17 Sep 2014 17:05:35 -0400<br>From: "Sean Hyde" <<a href="mailto:sean.a.hyde@gmail.com">sean.a.hyde@gmail.com</a>><br>To: <<a href="mailto:foss-gps@lists.osgeo.org">foss-gps@lists.osgeo.org</a>><br>Subject: [FOSS-GPS] Mobile Robot Experimentation<br>Message-ID: <0ddc01cfd2bb$20551d40$60ff57c0$@<a href="http://gmail.com" target="_blank">gmail.com</a>><br>Content-Type: text/plain; charset="us-ascii"<br><br>Hey Guys,<br><br><br><br>I've been playing around with RTKLib for a couple months now and have run<br>into some issues and I was wondering if anyone had any idea on how to<br>improve performance.<br><br><br><br>---Setup---<br><br>Base Station:<br><br>NVS08C on custom PCB using the receiver to power the antenna<br><br>Antenna is Taoglas Limited AA.161.301111<br>(<a href="http://www.taoglas.com/images/product_images/original_images/AA.161.301111.pdf" target="_blank">http://www.taoglas.com/images/product_images/original_images/AA.161.301111.<br>pdf</a>)<br><br>Antenna is on a 12" x 24" steel plate<br><br>Connected via FTDI->USB to Rasperry Pi<br><br>Raspberry Pi runs str2str to send the data to Windows laptop running rtknavi<br>using wifi backhaul<br><br><br><br>Rover:<br><br>NVS08C on custom PCB using the receiver to power the antenna<br><br>Antenna is Taoglas Limited AA.161.301111<br>(<a href="http://www.taoglas.com/images/product_images/original_images/AA.161.301111.pdf" target="_blank">http://www.taoglas.com/images/product_images/original_images/AA.161.301111.<br>pdf</a>)<br><br>Antenna is on a 18" x 18" steel plate<br><br>Connected via FTDI->USB to Rasperry Pi<br><br>Raspberry Pi runs str2str to send the data to Windows laptop running rtknavi<br>using wifi backhaul<br><br><br><br>The Rover setup is on a small mobile robot with a top speed of about 3mph.<br>It is in a city (Pittsburgh), but the sky is relatively unobstructed.<br><br><br><br>I'm running rtknavi in Kinematic mode using only GPS, L1+L2, 15deg elevation<br>mask. The position that I input for the base station is a 5 hour average<br>(though it seems to have lost some precision when I pasted it?). I have<br>tried both Continuous and Fix and Hold Integer Ambiguity Res. I'll try to<br>attach screen shots of rtknavi.<br><br><br><br>Right now, it kind of works. I can get relatively jitter-free floats and<br>occasionally fixes, but these fixes don't last long and I'm not sure they<br>are actually globally accurate (ie: if you restart the software, you may get<br>a fix, but it may be several meters from your last fix). Sometimes a fix<br>goes away and never seems to come back.<br><br><br><br>I'm wondering if you guys have any suggestions to improve these results.<br><br>Better antennas? (Which ones?)<br><br>Trying to get better placement of the base station?<br><br>Different settings in rtknavi?<br><br>Continuous vs Fix and Hold?<br><br><br><br>Thanks!<br><br>-Sean<br><br><br><br><br><br>-------------- next part --------------<br>An HTML attachment was scrubbed...<br>URL: <<a href="http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment.html" target="_blank">http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment.html</a>><br>-------------- next part --------------<br>A non-text attachment was scrubbed...<br>Name: image001.png<br>Type: image/png<br>Size: 25680 bytes<br>Desc: not available<br>URL: <<a href="http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment.png" target="_blank">http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment.png</a>><br>-------------- next part --------------<br>A non-text attachment was scrubbed...<br>Name: image002.png<br>Type: image/png<br>Size: 29201 bytes<br>Desc: not available<br>URL: <<a href="http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment-0001.png" target="_blank">http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment-0001.png</a>><br>-------------- next part --------------<br>A non-text attachment was scrubbed...<br>Name: image003.png<br>Type: image/png<br>Size: 26117 bytes<br>Desc: not available<br>URL: <<a href="http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment-0002.png" target="_blank">http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment-0002.png</a>><br>-------------- next part --------------<br>A non-text attachment was scrubbed...<br>Name: image004.png<br>Type: image/png<br>Size: 19442 bytes<br>Desc: not available<br>URL: <<a href="http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment-0003.png" target="_blank">http://lists.osgeo.org/pipermail/foss-gps/attachments/20140917/04981835/attachment-0003.png</a>><br><br>------------------------------<br><br>_______________________________________________<br>FOSS-GPS mailing list<br><a href="mailto:FOSS-GPS@lists.osgeo.org">FOSS-GPS@lists.osgeo.org</a><br><a href="http://lists.osgeo.org/mailman/listinfo/foss-gps" target="_blank">http://lists.osgeo.org/mailman/listinfo/foss-gps</a><br><br>End of FOSS-GPS Digest, Vol 68, Issue 7<br>***************************************<o:p></o:p></p></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></div></div></body></html>